Derrick



(No Model.)

DERRIGK.

Patented Mar. 12, 1895.

ETE

Critics.

DERRICK.

SPECIFICATION forming part of Letters Patent No. 535,537, dated March 12, 1895.

Application filed December 14, 1894. Serial No. 531,747. (No model.)

To all whom, t may concern,.-

Beit known that I, I-IERMON B. GATES, a citizen of the United States, residing at Edgewater, in the county of Bergen and State of New Jersey, have invented a certain new and useful Improvement in Derricks, of which the following is a specification.

The improvement relates particularly to the construction of the mast and boom. Each is an open framework, tapering in both di-` properly formed at'the ends to match closely to the sides thereof, leaving the center clear. Retaining rings, each of adiameter to match, are shrunk on at these points, binding the rails and inclosed spacing-blocks iirmly together. The whole forms an eminently strong and light construction, particularly well adapted for use on floating docks, lighters and similar vessels, and also in other situations where combined strength and lightness are desirable.

The boom is mounted on a ball-and-socket joint, set at an angle to allow the boom to be raised and lowered within wide limits without strain upon the neck.

The ends of the rails are enlarged and secured in a properly formed block by a cupshaped casting applied hot, and allowed to cool in place, forcibly locking the rail ends in the block and holding all fast.n Thecupshaped casting at the lower end of the boom carries the ball engaging in the socket. At the upper end a similar castingis provided with holes for the engagement of the hoisting blocks. v

The accompanying drawings form a part of this specification. .1

Figure 1 is an elevation. Fig52'is a side view of the boom attached, partly in longitudinal section. tions on a larger scale, on the lines 3-3 and 4-4 in Fig. 2. Figs. 5, 6 and 7 show one of the spacing-blocks. Fig-5 is a face view. Fig. 6 is an end view, and Fig. 7 is a section on the line 7-7 in Fig. 5. The remaining figures show details. Fig. 8 is a vertical section, partly in elevation, showing the ball-andsocket step for the boom. Fig. 9 is a section on the line 9-9 in Fig. 8. Fig. 10 is an end view of a portion alone. Fig. 11 is a side view of the same. Fig. 12 is an elevation, showing the means for securing the upper ends of the masts. Fig. 13 is a view of the same 'from above. Fig. 14 is a vertical section, partly in elevation, showing the step for one of the masts.

Similar letters of reference indicate like parts in all the figures.

Figs. 3 and 4 are cross-sec- A is the deck of the vessel, and A cast iron step-pieces iirmly secured to the timbers in which are set the masts B, B, inclined toward each other and joined at the upper ends.

The main features of construction of the boom and masts are identical, and a description of the boom will suffice for both, excepting in such particulars as will be designated. C is the boom, tapering in both directions from the mid-length, engaged at the base by a ball-and-socket joint.

C is the ball, connected by the'neck C2 to a casting C3. It is seated in the concave socket A2, secured to the deck timbers by bolts A3.

A4 is a cover made in halves, each bolted upon the socket casting to inclose the'ball, and provided with a sufficient opening to allow freedom of motion to the neck C2. The joint between the socket and its cover is inclined `downward and outward, as shown, to allow the boom to be depressed to a more nearly horizontal position than could be ordinarily obtained.

C4, C4, are the T-rails of rolled iron or steel, extending the entire length of the boom. Their ends are iiattened by upsetting, or othwise, and are engaged in blocks or end-pieces C5, C5, of cast iron, properly formed to receive them, and secured in place by cup-shaped castings of steel C3, O6, the former carrying the ball C', above described, and the latter carrying a flattened and widened portion, provided with two holes a, d', in which are ICO engaged the hooks of the elevating block for the boom yand the hoist-ing block for the load.

The rails are set'with the webs c, c, inward on radial lines toward the center. I have shown six rails, equally spaced, and separated each from the next by a segmental spacingblock D, filling the intermediate space between each rail and the next, having each end shaped, as shown, to match against the adjacent rail, so that when all are in place a section at this point shows a complete circle made up of the spacing-blocks and rails, lying metal to metal. (See Fig. 3.) The radial thickness of the blocks is the same as the depth of the rail through the web, and the width corresponds to that of a steel retaining ring E, which latter is slid into position while hot from one end of the boom. In cooling, the ring shrinks, forcing the inclosed rails and blocks into close contact with each other, and binding the whole securely.

There may be as many rings and sets of blocks as may be found necessary or desirable. I have shown nine, equally spaced, diminishing in diameter and also in width to correspond to the taper of the boom and to the/increased stiffness due to the gradual approach of the rails to each other toward the ends.

The masts are similar in general construction to the boom, but the rail ends are Welded to the end-pieces. The end-pieces B5, B5, at the upper ends are Iiattened, and provided with holes to receive bolts G extending through the downwardly inclined wings G2 of a cap forging G, provided on its under face with an abutment G3 separating the ends of the masts and taking the strain of compression at this point which would otherwise be borne by the bolts G.

Two rearwardly projecting lugs G4, G4, are each drilled to receive a guy-rope fastened to the deck, or other fixed portion.

An eye His mounted on the under side of the cap G, secured by nuts l'rI2 engaging the shank I-I, which latter extends upward through the cap and is threaded to receive the nuts.

Thelower end-pieces B3, B3, of the masts are cylindrical, and engaged in inclined sockets in the anchor-pieces A.

It will be understood that the guys, hoisting ropes, blocks, and hoisting enginemay be of any ordinary or suitable character, and are only partly represented in the drawings.

The blocks C5, C5, are each cast in the form shown in Figs. 9, 10 and ll, with longitudinal grooves c5, c5, to match the cross-section of the rails, and receive the latter so that their outer faces shall be about iiush with the snrface of the blocks. The grooves c5 are enlarged at one end, forming offsets c6, engaging the upset ends c4, c4, of therails and lock them against displacement longitudinally.

A steel casting C3 or C6 of proper inside diameter is then applied hot over the rail ends and block, and allowed to coolin position,

shrinking as it cools, thus joining the inclosed portions and itself firmly together.

The advantages of the construction will be readily appreciated. By dispensing with a central core and arranging the spacing-blocks in the form of hollow rings at suitable intervals, the whole interior is left clear, thus greatly reducing the weight without detracting from the strength or stiffness.

Modifications may be made in the details 4.without departing from the principle of the invention.

A greater or less number of T-rails may be employed with the spacing-blocks and rings set nearer together or at greater intervals than here shown, as may be found desirable or expedient in designing the derrick for carrying loads of greater orless weight. A boom sixty-live (65) feet in length, constructed in the proportions here shown, will safely sustain a loadI of sixty (60) tons.

The spacing -blocks D may be secured against liability to work loose by lightbolts engaging them with the rails, but I do not consider such necessary, as the shrinking of the inclosing ring in cooling compresses the parts into close contact with each other, and binds the whole with absolute iirmness. These blocks are for lightness cast hollow or open on one side, as shown, but may be solid, or otherwise formed, as the strength required to withstand the strain may determine.

Instead of the two masts shown, a single upright mast, properly guyed, may be employed if preferred.

I claim as my invention- 1. In a mast or boom for a` derrick or like structure, the T-rails extending lengthwise and arranged circumferentially with the mid- Wflange inward, separated from each other by segmental spacingblocks, in combination with the latter, and with the retaining ring embracing the rails and blocks, the whole forming a hollow framework, substantially as herein specified.

2. In a mast or boom for a derrick or like structure, the T-rails extending lengthwise and arranged circumferentially with the midlange inward, separated from each other by segmental spacing-blocks, having their ends formed to match to the contourof the adjoining rails, in combination. with each other, and with the retaining rings embracing the rails and blocks, and the end-pieces inclosed by the rail ends and secured thereto, the whole forming a hollow framework, substantially as herein specified.

3. In a boom for a derrick or like structure, the T-rails extendinglengthwise and-arranged circumferentially with the mid-flange inward, separated from each other by segmental spacing-blocks, in combination with the latter, and with the retaining rings shrunk upon the inclosed rails and. blocks, the end-pieces C5 grooved to receive the rail ends, and the inclosing castings Oa and C shrunk upon said IOO IZO

and outwardly, as shown, and the cover plates A4 and A4 applied on such surface, all ar- 15 ranged to allow a wide range of motion to the boom without cramping, substantially as herein specified.

In testimony that I claim the invention above set forth I affix my signature in pres zo ence of two witnesses.

IIERMON I5. GATES.

Witnesses:

CHAS. E. SEARLE, H. A. JOHNsToNE. 

